The invention relates generally to waste collection and removal systems. More particularly, the invention relates to systems for monitoring and managing the status of a number of waste containers, such as trash compactors, which are equipped with compacting assemblies, or open-top containers, which are not equipped with compacting assemblies, in a manner that permits a user to quickly determine at a central location the current status of all containers in the container network. The invention also relates to systems for managing communications between a central computer and a plurality of monitoring units, each located at a respective container site. The invention also relates to systems for permitting user-modified polling of such monitoring units.
Much effort has been invested to provide efficient and economical systems for facilitating waste collection from a network of waste containers. Typically, one or more waste collection service providers, or haulers, will service a waste container network that includes a large number of waste containers situated at different geographical locations in a given region. Usually, these containers are provided with a compacting device equipped with a hydraulic ram for compacting the trash or, they may consist of open-top containers which are not equipped with a compacting device. When a container becomes full, a hauler, typically a large truck, is dispatched to the site to empty the container. Since each hauler trip typically involves significant cost, and since the amount of waste generated at a particular location typically varies in an unpredictable manner, the status of each container in the network is usually monitored in some way to ensure that haulers are dispatched to full containers in a timely and economical manner.
It is known to provide waste container monitoring systems that employ a respective processing or monitoring unit and a respective communications link associated with each waste container. Such systems are disclosed in U.S. Pat. No. 5,303,642, the entire writing and subject matter of which are incorporated herein by reference. These systems detect container fullness by monitoring the maximum pressure applied to the hydraulic ram during a compaction stroke. The monitoring unit includes a microprocessor for making a container status, i.e., fullness or emptiness, determination. When a full or empty container determination is made, the monitoring unit initiates an outbound call and a signal representing the container status is communicated via communications link to a remote central location. For example, the monitoring unit initiates an outbound call when it determines that the associated container is full and sends a facsimile message to a remote location to indicate to a human administrator that a particular container is full or empty.
Other prior art systems, such as those disclosed in U.S. Pat. No. 5,016,197, provide an automated trash management system to monitor the fullness of a plurality of trash compactor/container units based upon an analysis of the number of cycles of the compactor and the hydraulic pressure associated therewith. Such systems utilize a monitoring unit that includes a pressure sensing unit associated with each waste container. The monitoring unit transmits data, representing instantaneous hydraulic pressures, to a central computer via communications link, such as a telephone system. The central computer determines the fullness of each trash compactor based on the transmitted pressure data. The computer may compile a database for each trash compactor and compactor fullness may be determined from the database.
As waste container networks grow in size, the management of the status information provided for each container in the container network becomes increasingly difficult. A human administrator of the container network is presented with and/or required to manage a great deal of information. Thus, a determination of which containers require immediate attention, i.e., which containers require emptying or are experiencing an error condition, often becomes overly burdensome. Accordingly, those of ordinary skill in the art will recognize a need for a system for facilitating the efficient management of a waste container network by providing comprehensive information in a manner that permits a human user to quickly and accurately determine the status of all containers in a container network. Moreover, there is a need for a system that is versatile in that it is compatible with monitoring units which make a fullness determination at the container site and with monitoring units which provide information used to make a fullness determination at a central computer.
Another problem with prior art waste container management systems is that they do not provide for real-time dynamic updating of container status. Nor do they provide for user-controlled polling of the containers in the network. For example, in systems such as the one disclosed in U.S. Pat. No. 5,016,197, where pressure readings are conveyed to a central computer, the central computer typically conducts polling of a particular container according to a preset and rigid schedule. Thus, in cases where a user desires immediate information about a container""s status, the information is not readily available until the container is polled by the system. Another related consequence of the prior art polling techniques is that the information presented to the user may not be accurate or up to date. Thus, it would be desirable to provide a waste management system which provides for real-time dynamic updating of container status and which permits a user to modify or control the polling schedule associated with particular containers.
Yet another problem with prior art waste container management systems is that they do not provide for efficient updating of container status information. In a typical prior art container network, the monitoring units will typically be adapted to make outbound calls to a central computer to report container status information. In addition, the central computer may be adapted to make outbound calls according to an automatic polling routine to update container status. However, if outbound calls are being made, the receipt of an inbound call from a full container in prior art systems may be prevented or delayed, especially in systems that provide only a single communications channel, resulting in outdated information being presented to the user. Thus, the prior art does not provide an efficient method for managing inbound and outbound calls in a manner that provides for efficient updating of container status information. Accordingly, there is a need for such a system.
The benefits and advantages described above are realized by the present invention which provides a system for remotely managing a network of waste containers in a container network which provides comprehensive container network information to a user in a manner that enables the user to quickly and accurately determine the status of all containers in the container network. In a preferred embodiment, the invention provides a central computer having a communication link to each of the monitoring units for the respective containers in the container network. Communications with the monitoring units in the container network are managed by a communications module on the central computer. The central computer is adapted to provide a dynamically updated display which distinguishes full containers from other containers in the network. In a preferred embodiment, the invention provides a graphic display with a full container window or zone in which identifiers for the full containers displayed, along with other information, such as container location, pressure and compaction readings, account information and contact information for the waste collection service or hauler associated with the container. The display is provided by a display module in conjunction with a full container module which cooperates with a container database to determine which containers in the container network have reported full status and periodically redraws the full container zone or window to provide an updated list of full containers.
The container database preferably includes a container table and a transaction table. The container table is a relatively static database containing a container record for each container in the network. Each container record includes a container identifier and various information associated with the container, including operating parameters, accounting information and geographical location. In a preferred embodiment, the container record includes a full status flag which is used to indicate whether a fullness determination has been made by the monitoring unit associated with the container and communicated to the central computer. Alternatively, the container record may include a pressure threshold and a fullness determination may be made at the central computer. The transactions table is a relatively dynamic database and contains transaction records resulting from each communication session attempted or established with a monitoring unit in the container network. Each transaction record contains information identifying the associated container, as well as information identifying the type of transaction resulting from the communication attempt with the monitoring unit associated with the container.
The invention also provides an alarm zone or window for distinguishing to the user which containers in the container network have an alarm condition. The transaction table is adapted to contain transaction types that include errors that occur during communication attempts. An alarm module cooperates with the transaction table to determine which containers have an alarm condition and, in conjunction with the display module, provides a graphic display listing identifiers for the containers with an alarm condition. Like the full container module, the alarm module periodically reviews the container database and updates the alarm zone or window to reflect the current status of the containers in the container network.
The invention also provides a container status zone or window for displaying the non-full containers which do not have an alarm condition. A container status module cooperates with the transaction table to determine which containers are neither full nor have an alarm condition and, in conjunction with the display module, provides a graphic display listing identifiers for the containers that are neither full nor have an alarm condition.
The full container zone, alarm zone and container status zone of the invention provide a simple and efficient way for an operator to quickly determine the status of all containers in the container network. Moreover, the full container zone distinguishes full containers from the rest of the containers in the container network such that the user may quickly determine which containers are in need of emptying. Similarly, the alarm zone distinguishes containers having an alarm condition from the rest of the containers in the network and permits quick determination by a user of containers experiencing an error condition.
According to yet another feature of the invention, automatic polling may be scheduled by the user. Polling involves an outbound call or communication initiated by the central computer to the monitoring unit for a selected container in the container network. A polling module provides a user interface to enable a user to enter polling parameters and the polling module updates the container database accordingly. The container records stored in the container table preferably contain fields for an automatic polling flag and a polling interval. The polling module accepts user input and stores the appropriate automatic polling data in the container record. The communications module is adapted to periodically review the container table and schedule polling sessions according to the parameters in the automatic polling flag and polling interval fields in the container records. Preferably, the polling sessions are queued into a session stack on a first-in-first-out basis. In this manner, the user can control the polling interval for each container in the container network. Moreover, the session stack permits scheduled polling sessions, as well as on-demand polling sessions requested by the user, to be queued such that the user need not be present for the polling sessions to be performed. The communications module conducts polling of the containers in the network in a manner that is preferably transparent during the user""s observation of the full container zone, container status zone and alarm zone. The communications module is preferably implemented as a communications thread that is separate from and executed in the background relative to the main thread of execution represented by the operation of the full container module, container status module and alarm module.
According to yet another feature of the invention, the communications module is adapted to manage the scheduling and execution of polling sessions while permitting the receipt of inbound full or empty calls initiated by monitoring units in the container network. The communications module provides a waiting period or delay between the execution of scheduled polling events to permit receipt of inbound calls. Preferably, the receipt of an inbound call preempts the polling events already queued in the session stack such that the calling session associated with the inbound call is performed immediately. This ensures that inbound calls from monitoring units, for example, inbound calls indicative of a full container in the network, result in immediate updating of the container database and immediate appropriate updating of the full container zone, container status zone or alarm zone.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention, from the claims, and from the accompanying drawings.